I'm Peter Roberts, immigration attorney who does work for YC and startups. AMA

Hello HN! It's been about 9 months since we've done one of these and it seems like time for another. Previous threads we've done: https://news.ycombinator.com/submitted?id=proberts . I'll be here for the next 2-3 hours and then after a break of about 1 hour for another 2-3 hours. As usual, there are many possible topics and I'll be guided by whatever you're concerned with. Please remember that I can't provide legal advice on specific cases for obvious liability reasons because I won't have access to all the facts. Please stick to a factual discussion in your questions and comments and I'll try to do the same in my answers!